HD6417020SVX12I Renesas Electronics America, HD6417020SVX12I Datasheet - Page 354

• Manufacturer Part Number: HD6417020SVX12I
• Description: IC SUPERH MPU ROMLESS 100TQFP
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH7020r

Specifications of HD6417020SVX12I

• Core Processor: SH-1
• Core Size: 32-Bit
• Speed: 12.5MHz
• Connectivity: EBI/EMI, SCI
• Peripherals: DMA, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Type: ROMless
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Program Memory Size: -
• Data Converters: -

12.3.2
To use the WDT as an interval timer, clear WT/IT to 0 and set TME to 1. An interval timer
interrupt (ITI) is generated each time the timer counter overflows. This function can be used to
generate interval timer interrupts at regular intervals (figure 12.5).
12.3.3
The watchdog timer has a special function to clear the standby mode with an NMI interrupt. When
using the standby mode, set the WDT as described below.
Transition to the Standby Mode: The TME bit in the TCSR must be cleared to 0 to stop the
watchdog timer counter before it enters the standby mode. The chip cannot enter the standby mode
while the TME bit is set to 1. Set bits CKS2–CKS0 so that the counter overflow interval is equal
to or longer than the oscillation settling time. See section 20.3, AC Characteristics, for the
oscillation settling time.
Recovery from the Standby Mode: When an NMI request signal is received in standby mode,
the clock oscillator starts running and the watchdog timer starts counting at the rate selected by
bits CKS2–CKS0 before the standby mode was entered. When the TCNT overflows (changes
from H'FF–H'00), the system clock ( ) is presumed to be stable and usable; clock signals are
supplied to the entire chip and the standby mode ends.
For details on the standby mode, see section 19, Power Down States.
RENESAS 336
H'FF
H'00
TCNT value
WT/IT = 0
Operation in the Interval Timer Mode
Operation in the Standby Mode
TME = 1
Figure 12.5 Operation in the Interval Timer Mode
Overflow
ITI
Overflow
ITI
Overflow
ITI
Overflow
ITI
Time